Characterization of the Major Odorants in Cempedak-Differences to Jackfruit

Screening the volatiles of cempedak [Artocarpus integer (Thunb.) Merr.] pulp for odor-active compounds by aroma extract dilution analysis and gas chromatography (GC)-olfactometry of static headspace samples revealed a total of 55 odorants, among which 47 were identified. Using stable isotopically substituted odorants as internal standards, these compounds were quantitated by GC-mass spectrometry, and odor activity values (OAVs) were calculated as ratios of the natural concentrations in cempedak pulp to the orthonasal odor detection thresholds. An aroma reconstitution model based on the 41 compounds with OAVs >1 in their natural concentrations successfully mimicked the characteristic aroma of cempedak pulp including the pronounced sulfury, oniony note which is intense in cempedak pulp but absent in jackfruit pulp. Further sensory tests finally showed that 2-(methylsulfanyl)propane, 2-(methylsulfanyl)butane, and 2-(methylsulfanyl)pentane are the key compounds responsible for this unique aroma note in cempedak pulp and vitally contribute to the aroma difference between cempedak pulp and jackfruit pulp.